]> > Weird ... I was going to suggeest it was because you weren't flushing > the output after each print statement. This raises important question: Let's see the output as a sequence of bytes (there's no time). Assuming that the process exits normally and incompatible printing functions are not mixed: is there a guarantee (in OCaml library) that the flush operation doesn't affect the output? For me it's obvious that the output shouldn't depend on the presence of flush operations. If otherwise - needs to be explicitly stated. (Of course I'm not considering the one special flush action done when closing a stream, but it's tied to the closing function.) Dawid